# Licorice Root (Glycyrrhiza glabra)

**Canonical URL:** https://ingredients.hermeticasuperfoods.com/ingredients/licorice-root
**Data Source:** Hermetica Superfoods Ingredient Encyclopedia
**Updated:** 2026-03-19
**Evidence Score:** 6 / 10
**Category:** Traditional Chinese Medicine
**Also Known As:** Glycyrrhiza glabra, Sweet root, Liquorice, Gan cao, Yashtimadhu, Spanish licorice, European licorice

## Overview

Licorice root (Glycyrrhiza glabra) contains glycyrrhizin, a triterpene saponin that inhibits viral replication and modulates inflammatory responses. Clinical studies demonstrate its effectiveness in reducing COVID-19 symptoms and ICU stay duration through [anti-inflammatory](/ingredients/condition/inflammation) and [antiviral](/ingredients/condition/immune-support) mechanisms.

## Health Benefits

• COVID-19 symptom relief: Open-label RCT showed improvements in fever, cough, and inflammatory markers within 7 days (PMID: 32933552)
• Reduced ICU stay: Double-blind RCT (n=52) found 760mg daily reduced ICU length and improved oxygen saturation in critically ill COVID-19 patients (PMID: 39262414)
• Oral ulcer healing: Systematic review of 6 trials (n≈244) demonstrated topical licorice (1-5%) reduced pain and ulcer size significantly (P<0.01) within 4-8 days
• NAFLD improvement: 12-week RCT in women showed significant improvements in ALT (p<0.001), [insulin resistance](/ingredients/condition/weight-management), and hepatic steatosis (PMID: 35785498)
• [Anti-inflammatory](/ingredients/condition/inflammation) effects: Multiple studies confirm suppression of NF-κB, TNF-α, IL-6, and COX-2/PGE2 pathways

## Mechanism of Action

Glycyrrhizin inhibits viral replication by blocking viral entry and interfering with RNA synthesis. It suppresses [pro-inflammatory cytokine](/ingredients/condition/inflammation)s like IL-6 and TNF-α while inhibiting 11β-hydroxysteroid dehydrogenase, leading to [cortisol](/ingredients/condition/stress)-like anti-inflammatory effects. The compound also modulates NF-κB signaling pathway to reduce inflammatory responses.

## Clinical Summary

Open-label RCT evidence shows licorice root improves COVID-19 symptoms including fever and cough within 7 days, with measurable reductions in [inflammatory](/ingredients/condition/inflammation) markers. A double-blind RCT with 52 critically ill COVID-19 patients found 760mg daily significantly reduced ICU length of stay and improved oxygen saturation. While promising, the evidence base remains limited to COVID-19 studies with small sample sizes. Additional research is needed to establish broader therapeutic applications.

## Nutritional Profile

{"macronutrients": {"carbohydrates": "53g per 100g", "protein": "0.2g per 100g", "fiber": "0.2g per 100g"}, "micronutrients": {"calcium": "91mg per 100g", "iron": "0.05mg per 100g", "magnesium": "37mg per 100g", "potassium": "37mg per 100g", "sodium": "50mg per 100g"}, "bioactive_compounds": {"glycyrrhizin": "2-25% depending on preparation", "flavonoids": "0.5-1% including liquiritin and isoliquiritin"}, "bioavailability_notes": "Glycyrrhizin is well-absorbed but can be metabolized to glycyrrhetinic acid, which may affect mineralocorticoid activity. Flavonoids have moderate bioavailability, influenced by gut microbiota."}

## Dosage & Preparation

Oral: 760mg standardized extract tablets daily for acute conditions (5 days). Topical: 1-5% extract in patches or pastes applied 4 times daily for 5-8 days. Chronic conditions: Unspecified powder dose for 12 weeks. Limit glycyrrhizic acid intake to less than 100mg daily to avoid adverse effects. Consult a healthcare provider before starting any new supplement.

## Safety & Drug Interactions

Licorice root can cause pseudoaldosteronism, leading to hypertension, hypokalemia, and fluid retention with prolonged use. It may interact with [blood pressure](/ingredients/condition/heart-health) medications, diuretics, and corticosteroids by potentiating their effects. Contraindicated in pregnancy due to potential premature labor risk and in patients with cardiovascular disease or kidney disorders. Daily intake should not exceed 100mg glycyrrhizin for extended periods.

## Scientific Research

Clinical evidence includes a double-blind RCT (n=52) showing 760mg D-reglis® licorice tablets reduced ICU stay in COVID-19 patients (PMID: 39262414), and a systematic review of 6 trials demonstrating topical licorice's efficacy for recurrent aphthous stomatitis. An RCT in women with NAFLD found 12 weeks of licorice powder improved liver enzymes and [insulin resistance](/ingredients/condition/weight-management) (PMID: 35785498).

## Historical & Cultural Context

Glycyrrhiza glabra has been used for millennia in Traditional Chinese Medicine (as gan cao for harmonizing formulas), Ayurveda (yashtimadhu for throat/respiratory issues), and Greco-Arabic systems for cough, digestive ulcers, and liver diseases. Historical records date to ancient Egypt and China's Shennong Bencao Jing (~2000 years ago) for expectorant and [anti-inflammatory](/ingredients/condition/inflammation) purposes.

## Synergistic Combinations

Ginger root, Marshmallow root, Slippery elm, Milk thistle, N-acetylcysteine

## Known Interactions

| Substance | Severity | Summary | URL |
|---|---|---|---|
| Pomegranate | SAFE | 🟢 SAFE — Licorice Root and Pomegranate can be taken together safely. | https://ingredients.hermeticasuperfoods.com/interactions/pomegranate |
| Diphenhydramine | SAFE | 🟢 SAFE — Licorice Root and Diphenhydramine can be taken together safely. | https://ingredients.hermeticasuperfoods.com/interactions/diphenhydramine |
| Dextromethorphan | SAFE | 🟢 SAFE — Licorice Root and Dextromethorphan can be taken together safely. | https://ingredients.hermeticasuperfoods.com/interactions/dextromethorphan |
| Pseudoephedrine | SAFE | 🟢 SAFE — Licorice Root and Pseudoephedrine can be taken together safely. | https://ingredients.hermeticasuperfoods.com/interactions/pseudoephedrine |
| Phenylephrine | SAFE | 🟢 SAFE — Licorice Root and Phenylephrine can be taken together safely. | https://ingredients.hermeticasuperfoods.com/interactions/phenylephrine |
| Guaifenesin | SAFE | 🟢 SAFE — Licorice Root and Guaifenesin can be taken together safely. | https://ingredients.hermeticasuperfoods.com/interactions/guaifenesin |
| Bismuth Subsalicylate | SAFE | 🟢 SAFE — Licorice Root and Bismuth Subsalicylate can be taken together safely. | https://ingredients.hermeticasuperfoods.com/interactions/bismuth-subsalicylate |
| Meclizine | SAFE | 🟢 SAFE — Licorice Root and Meclizine can be taken together safely. | https://ingredients.hermeticasuperfoods.com/interactions/meclizine |
| Docusate | SAFE | 🟢 SAFE — Licorice Root and Docusate can be taken together safely. | https://ingredients.hermeticasuperfoods.com/interactions/docusate |
| Polyethylene Glycol | SAFE | 🟢 SAFE — Licorice Root and Polyethylene Glycol can be taken together safely. | https://ingredients.hermeticasuperfoods.com/interactions/polyethylene-glycol |
| Simethicone | SAFE | 🟢 SAFE — Licorice Root and Simethicone can be taken together safely. | https://ingredients.hermeticasuperfoods.com/interactions/simethicone |
| Calcium Carbonate | SAFE | 🟢 SAFE — Licorice Root and Calcium Carbonate can be taken together safely. | https://ingredients.hermeticasuperfoods.com/interactions/calcium-carbonate |
| Magnesium Hydroxide | SAFE | 🟢 SAFE — Licorice Root and Magnesium Hydroxide can be taken together safely. | https://ingredients.hermeticasuperfoods.com/interactions/magnesium-hydroxide |
| Phenazopyridine | SAFE | 🟢 SAFE — Licorice Root and Phenazopyridine can be taken together safely. | https://ingredients.hermeticasuperfoods.com/interactions/phenazopyridine |
| Minoxidil | SAFE | 🟢 SAFE — Licorice Root and Minoxidil can be taken together safely. | https://ingredients.hermeticasuperfoods.com/interactions/minoxidil |
| Benzoyl Peroxide | SAFE | 🟢 SAFE — Licorice Root and Benzoyl Peroxide can be taken together safely. | https://ingredients.hermeticasuperfoods.com/interactions/benzoyl-peroxide |
| Salicylic Acid | SAFE | 🟢 SAFE — Licorice Root and Salicylic Acid can be taken together safely. | https://ingredients.hermeticasuperfoods.com/interactions/salicylic-acid |
| Hydrocortisone | SAFE | 🟢 SAFE — Licorice Root and Hydrocortisone can be taken together safely. | https://ingredients.hermeticasuperfoods.com/interactions/hydrocortisone |
| Cranberry Extract | SAFE | 🟢 SAFE — Licorice Root and Cranberry Extract can be taken together safely. | https://ingredients.hermeticasuperfoods.com/interactions/cranberry-extract |
| Apple Cider Vinegar | SAFE | 🟢 SAFE — Licorice Root and Apple Cider Vinegar can be taken together safely. | https://ingredients.hermeticasuperfoods.com/interactions/apple-cider-vinegar |

## Frequently Asked Questions

### How much licorice root should I take for immune support?

Clinical studies used 760mg daily for COVID-19 patients, but safe long-term dosing is typically limited to amounts providing less than 100mg glycyrrhizin daily. Consult a healthcare provider for personalized dosing recommendations.

### Can licorice root raise blood pressure?

Yes, licorice root can significantly raise blood pressure by mimicking aldosterone effects, causing sodium retention and potassium loss. This effect is dose-dependent and can occur within weeks of regular use.

### Does licorice root interact with blood pressure medications?

Licorice root can counteract blood pressure medications and enhance diuretic effects, potentially causing dangerous electrolyte imbalances. It may also increase the risk of digoxin toxicity through potassium depletion.

### Is DGL licorice safer than regular licorice root?

DGL (deglycyrrhizinated licorice) has glycyrrhizin removed, eliminating blood pressure and electrolyte concerns. However, DGL may not provide the same antiviral and anti-inflammatory benefits seen in COVID-19 studies.

### How long can I safely take licorice root supplements?

Regular licorice root use should be limited to 4-6 weeks maximum due to pseudoaldosteronism risk. Longer use requires medical supervision with regular blood pressure and electrolyte monitoring.

### What does clinical research show about licorice root for COVID-19 symptoms?

An open-label RCT demonstrated that licorice root improved fever, cough, and inflammatory markers within 7 days in COVID-19 patients. A double-blind RCT with 52 critically ill COVID-19 patients found that 760mg daily of licorice root reduced ICU length of stay and improved oxygen saturation levels. While these results are promising, more large-scale trials are needed to establish licorice root as a standard supportive therapy.

### Is licorice root safe for pregnant women or children?

Licorice root is generally not recommended during pregnancy due to potential effects on fetal development and increased blood pressure risk, which can complicate pregnancy outcomes. For children, licorice root should only be used under professional supervision and at appropriately reduced doses, as children may be more sensitive to its mineralocorticoid effects. Pregnant women and parents considering licorice for children should consult a healthcare provider first.

### What is the difference between topical licorice and oral licorice root supplements?

Topical licorice (1-5% concentration) is applied directly to oral ulcers and has demonstrated efficacy in healing based on a systematic review of 6 trials involving approximately 244 patients, with effects localized to the treatment area. Oral licorice root supplements are ingested systemically and provide broader effects on immune function, inflammation, and respiratory health, but carry higher risks of systemic side effects like elevated blood pressure. The choice between topical and oral depends on whether you're treating localized mouth ulcers or seeking systemic health benefits.

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*Source: Hermetica Superfoods Ingredient Encyclopedia — https://ingredients.hermeticasuperfoods.com*
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